The present disclosure broadly relates to the art of spring devices and, more particularly, to a gas spring and gas damper assembly as well as a vehicle suspension system and a method of operating such a gas spring and gas damper assembly.
A suspension system, such as may be used in connection with motorized vehicles, for example, can include one or more spring elements for accommodating forces and loads associated with the operation and use of the corresponding device (e.g., a motorized vehicle) to which the suspension system is operatively connected. In such applications, it is often considered desirable to utilize spring elements that operate at a lower spring rate, as a reduced spring rate can favorably influence certain performance characteristics, such as vehicle ride quality and comfort, for example. That is, it is well understood in the art that the use of a spring element having a higher spring rate (i.e. a stiffer spring) will transmit a greater magnitude of inputs (e.g., road inputs) to the sprung mass and that, in some applications, this could undesirably affect the sprung mass, such as, for example, by resulting in a rougher, less-comfortable ride of a vehicle. Whereas, the use of spring elements having lower spring rates (i.e., a softer or more-compliant spring) will transmit a lesser amount of the inputs to the sprung mass.
Such suspension systems also commonly include one or more dampers or damping components that are operative to dissipate energy associated with undesired inputs and movements of the sprung mass, such as road inputs occurring under dynamic operation of a vehicle, for example. Typically, such dampers are liquid filled and operatively connected between a sprung and unsprung mass, such as between a body and axle of a vehicle, for example. One example of such damping components are conventional shock absorbers that are commonly used in vehicle suspension systems.
In other arrangements, however, the dampers or damping components can be of a type and kind that utilizes gas rather than liquid as the working medium. In such known constructions, the gas damper portion permits gas flow between two or more volumes of pressurized gas, such as through one or more orifices, as shown, for example, in U.S. Patent Application Publication No. 2004/0124571, or through one or more valve ports, as shown, for example, in U.S. Patent Application Publication No. 2003/0173723. Generally, there is some resistance to the movement of pressurized gas through these passages or ports, and this resistance acts to dissipate energy associated with the gas spring portion and thereby provide some measure of damping.
One factor that may be limiting the broader adoption and use of gas spring and gas damper assemblies relates to the significant travel of which gas spring devices are capable. That is, gas spring devices are capable of being displaced between a minimum or compressed height and a maximum or extended height and the difference in these overall heights can be substantial.
Certain difficulties relating to the incorporation of gas dampers into gas spring devices have been associated with the aforementioned differences in overall height of gas spring devices. At one extreme, the minimum or compressed height of a gas spring device will act to limit the overall length of components that can be housed within the gas spring device. At the other extreme, any components housed within the gas spring device should remain operatively connected between the opposing end members of the gas spring device in the extended condition thereof.
Accordingly, it is believed desirable to develop a gas spring and gas damper assembly as well as a suspension system and method of assembly that further contribute to the art and, potentially, overcome one or more of the foregoing (e.g., issues relating to the achievement of targeted spring rates, the achievement of targeted of damping performance and/or the achievement of targeted travel capabilities) and/or other difficulties associated with known constructions (e.g., issues relating to cost of manufacture, process of assembly and/or robustness of design).